Oxford Sigma

Oxford Sigma is an internationally recognised advanced materials company focused on fusion, nuclear, and defence systems. Founded in 2019, we were established to support the commercial deployment of fusion energy by addressing the critical challenge of developing sustainable, high-performance materials for extreme environments.

We believe that the future of fusion energy, nuclear fission, and high-energy systems depends on materials that can withstand the harshest environments. By designing and validating these materials, we enable technologies that support energy security, national resilience, and climate action—always grounded in scientific integrity and engineering excellence.

Our vision is to accelerate the deployment of energy and defence systems that strengthen energy security and national resilience. We focus on enabling commercialisation through leadership in international standardisation, the development of advanced materials for extreme radiation and temperature conditions, and strategic innovation in materials engineering.

We pursue practical yet ambitious targets in materials selection and development for extreme environments—across fusion energy, advanced nuclear, and high-impact defence systems. Our approach is technology-agnostic and grounded in scientific rigor, engineering integrity, and pragmatic design. This enables us and our partners to make sound design choices, deliver advanced materials systems, and accelerate the de-risking of technology deployment.

Mélanie leads Oxford Sigma’s commercial activities, spanning marketing, sales, product development, and pricing, while fostering strong stakeholder relationships. She is currently studying for an Executive MBA and holds an MEng in Mechanical Engineering from a French Engineering School and an MSc in Aerospace Vehicle Design from Cranfield University.

Oxford Sigma have collected over 100 years of experience in fusion and closely related extreme environments. Across our domain expertise, we cover the fusion materials, processing, application, testing and simulation spaces.

Partnerships and collaborations are at the core of our ethos. Fusion and other extreme environment challenges are unlikely to be solved in isolation. ​

​S ee our latest updates on our progression for more details on our current partnerships. Contact us if you would like to partner to solve a challenge with materials. ​

At Oxford Sigma, we deliver advanced materials technology and engineering solutions that accelerate the commercialisation of fusion energy and other extreme environment applications. Our core strengths include:

We design, assess, and deploy next-generation materials built to perform in the world’s harshest environments. Our expertise spans fusion, nuclear, and high-performance industrial sectors.

We lead pioneering research and development programmes that push the boundaries of materials science and manufacturing. Our work is grounded in robust engineering and materials substantiation, ensuring that innovations are not only novel but also technically and commercially viable.

We rigorously test and validate advanced materials to ensure performance under extreme thermal, mechanical, and radiation conditions. Oxford Sigma also leads the development of international standards, helping shape the frameworks that govern the future of fusion and advanced materials technologies.

Oxford Sigma has been awarded the Ministry of Defence Employer Recognition Scheme (ERS) Gold Award, recognising its outstanding commitment to supporting the Armed Forces community.

Oxford Sigma has commissioned in-house manufacturing capabilities for advanced materials, enabling rapid iteration, scale-up, and supply.

Oxford Sigma, in partnership with the Rockwood Group, is delivering a Sub Scale Model Coil for UK Fusion Energy that will enable critical magnet testing for STEP and enable delivery of the first STEP technical milestone of the UK Fusion Strategy in 2026.